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Structural Durability & Health Monitoring 2025年第1期19卷 25-54页

作者： Chao Zhang Shang-xi Lai Hua-Ping Wang School of Civil Engineering and Mechanics Lanzhou UniversityLanzhou730000China key laboratory of Special functional materials and Structural Design Ministry of EducationLanzhou UniversityLanzhou730000China

Modal parameters can accurately characterize the structural dynamic properties and assess the physical state of the ***,it is particularly signiﬁcant to identify the structural modal parameters according to the monitoring data information in the structural health monitoring(SHM)system,so as to provide a scientiﬁc basis for structural damage identiﬁcation and dynamic model modiﬁ*** view of this,this paper reviews methods for identifying structural modal parameters under environmental excitation and brieﬂy describes how to identify structural damages based on the derived modal *** paper primarily introduces data-driven modal parameter recognition methods(e.g.,time-domain,frequency-domain,and time-frequency-domain methods,etc.),brieﬂy describes damage identiﬁcation methods based on the variations of modal parameters(e.g.,natural frequency,modal shapes,and curvature modal shapes,etc.)and modal validation methods(e.g.,Stability Diagram and Modal Assurance Criterion,etc.).The current status of the application of artiﬁcial intelligence(AI)methods in the direction of modal parameter recognition and damage identiﬁcation is further *** on the pre-vious analysis,the main development trends of structural modal parameter recognition and damage identiﬁcation methods are given to provide scientiﬁc references for the optimized design and functional upgrading of SHM systems.

关键词： Structural health monitoring data information modal parameters damage identiﬁcation AI method

Multiple Tin Compounds Modified Carbon Fibers to Construct Heterogeneous Interfaces for Corrosion Prevention and Electromagnetic Wave Absorption

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Nano-Micro Letters 2025年第1期17卷 507-527页

作者： Zhiqiang Guo Di Lan Zirui Jia Zhenguo Gao Xuetao Shi Mukun He Hua Guo Guanglei Wu Pengfei Yin College of Science Sichuan Agricultural UniversityYa’an 625014People’s Republic of China School of materials Science and Engineering Hubei University of Automotive TechnologyShiyan 442002People’s Republic of China Institute of materials for Energy and Environment State Key Laboratory of Bio‑Fibers and Eco‑TextilesCollege of Materials Science and EngineeringQingdao UniversityQingdao 266071People’s Republic of China Shaanxi key laboratory of Macromolecular Science and Technology School of Chemistry and Chemical EngineeringNorthwestern Polytechnical UniversityXi’anShaanxi 710072People’s Republic of China

Currently,the demand for electromagnetic wave(EMW)absorbing materials with specific functions and capable of withstanding harsh environments is becoming increasingly ***-component interface engineering is considered an effective means to achieve high-efficiency EMW ***,interface modulation engineering has not been fully discussed and has great potential in the field of EMW *** this study,multi-component tin compound fiber composites based on carbon fiber(CF)substrate were prepared by electrospinning,hydrothermal synthesis,and high-temperature thermal *** utilizing the different properties of different substances,rich heterogeneous interfaces are *** effectively promotes charge transfer and enhances interfacial polarization and conduction *** prepared SnS/SnS_(2)/SnO_(2)/CF composites with abundant heterogeneous interfaces have and exhibit excellent EMW absorption properties at a loading of 50 wt%in epoxy *** minimum reflection loss(RL)is−46.74 dB and the maximum effective absorption bandwidth is 5.28 ***,SnS/SnS_(2)/SnO_(2)/CF epoxy composite coatings exhibited long-term corrosion resistance on Q235 steel ***,this study provides an effective strategy for the design of high-efficiency EMW absorbing materials in complex and harsh environments.

关键词： Electrostatic spinning Component regulation Heterogeneous interfaces Electromagnetic wave absorption Corrosion protection

Hierarchical porous(Ta_(0.2)Nb_(0.2)Ti_(0.2)Zr_(0.2)Hf_(0.2))C high-entropy ceramics prepared by a self-foaming method for thermal insulation

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Journal of Advanced Ceramics 2024年第7期13卷 956-966页

作者： Cuiyan Li Ruinan Gao Haibo Ouyang Tianzhan Shen Zihao Chen Yanlei Li key laboratory for green Manufacturing&functional Application of Inorganic materials School of Materials Science and EngineeringShaanxi University of Science and TechnologyXi’an 710021China

To meet the emerging demands for thermal protection materials for hypersonic aircraft,developing porous ultrahigh-temperature ceramics with both robust mechanical properties and superior thermal insulation performance is a critical ***,we report novel porous(Ta_(0.2)Nb_(0.2)Ti_(0.2)Zr_(0.2)Hf_(0.2))C high-entropy carbide(PHEC)ceramics fabricated by a self-foaming method using commercially available metal chloride and furfuryl alcohol(FA)as *** PHEC ceramics are constructed of microspheres with a size of 2µm,leading to a high porosity of 91.3%and an interconnected *** microspheres consist of high-entropy carbide grains(20 nm),resulting in abundant interfaces and nanosized pores in the PHEC *** to its unique hierarchical structure,the prepared PHEC ceramics have outstanding compressive strength(28.1±2 MPa)and exceptionally low thermal conductivity(κ_(T),0.046 W·m^(-1)·K^(-1))at room *** makes it a promising thermal insulation materials for ultrahigh temperature *** work provides a cost-effective and facile strategy for producing porous ultrahigh-temperature ceramics.

关键词： porous ceramics high-entropy carbides hierarchical structure thermal insulation self-foaming

N-Heterocyclic carbene-stabilized platinum nanoparticles within a porphyrinic nanocage for selective photooxidation

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Science China Chemistry 2023年第3期66卷 778-782页

作者： Yi-Shou Wang Hao Li Sha Bai Yao-Yu Wang Ying-Feng Han key laboratory of Synthetic and Natural functional Molecule of the Ministry of Education Xi’an Key Laboratory of Functional Supramolecular Structure and MaterialsCollege of Chemistry and Materials ScienceNorthwest UniversityXi’an 710127China

The successful construction of highly stable and active platinum nanoparticles(Pt NPs) within the confined cavity of a threedimensional porphyrinic nanocage is presented in this study. The flexible porphyrinic nanocage containing eight N-heterocyclic carbene(NHC) precursors was prepared using a metal-carbene-templated ring-closing metathesis(RCM) approach as new capping materials for the fabrication/stabilization of Pt NPs. Notably, the NHC-stabilized Pt NPs within the porphyrinic nanocage exhibited high catalytic activity for selective oxidation of 2-chloroethyl ethyl sulfide to nontoxic 2-chloroethyl ethyl sulfoxide with excellent stability and recyclability.

关键词： polycarbenes porphyrinic cage nanoparticles photocatalysis

Supramolecular polymer network constructed by a functionalized polyimidazolium salt derived from metal-carbene template approach

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Science China Chemistry 2024年第4期67卷 1224-1228页

作者： Ming-Ming Gan Zi-En Zhang Yi-Fan Zhang Heng Zhang Li-Ying Sun Ying-Feng Han key laboratory of Synthetic and Natural functional Molecule Chemistry of the Ministry of Education Xi’an Key Laboratory of Functional Supramolecular Structure and MaterialsCollege of Chemistry and Materials ScienceNorthwest UniversityXi’an 710127China

In this study,we present a supramolecular templating approach for constructing polyimidazolium salt containing crown ether and cyclobutane *** strategy involves the formation of metal-carbene templates,photochemical cycloaddition,and subsequent demetallation of metal *** by the host-guest chemistry between crown ether units and ammonium salts,we successfully fabricated a supramolecular polymer SPN1,which features imidazolium receptors and cyclobutane *** obtained SPN1 demonstrates outstanding reversible stimulus-response,antibacterial behavior and conductivity.

关键词： metal-carbene template crown ether polyimidazolium salt host-guest chemistry

Phase-mediated controllable intramolecular and intermolecular photocycloadditions assisted by supramolecular templates

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Science China Chemistry 2022年第6期65卷 1129-1133页

作者： Yi-Shou Wang Li-Ying Sun Yao-Yu Wang Ying-Feng Han key laboratory of Synthetic and Natural functional Molecule Chemistry of the Ministry of Education Xi’an Key Laboratory of Functional Supramolecular Structure and MaterialsCollege of Chemistry and Materials ScienceNorthwest UniversityXi’an710127China

Understanding and controlling supramolecular template effect assembly via a photochemical reaction in different solid and solution phases is one of the main topics in photochemistry. Here, an interesting case of phase-mediated controllable intramolecular/intermolecular photochemical [2+2] cycloadditions assisted by supramolecular templates was demonstrated. Direct irradiation of the complexes in solution yields intramolecular photoproducts exclusively, whereas exposure of the solid powder sample under the same conditions yields intermolecular dinuclear species quantitatively. The nature of the phase and supramolecular interaction affects the geometrical arrangements of the metallacycles, leading to different cycloaddition products under photoirradiation. The crystal structures of different products were investigated by single-crystal X-ray diffraction, nuclear magnetic resonance(NMR) spectrometry, and electrospray ionization mass spectrometry(ESI-MS).

关键词： N-heterocyclic carbene photochemical cycloaddition template synthesis topochemistry stacking interactions

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A novel colorimetric and ratiometric NIR fluorescent sensor for glutathione based on dicyanomethylene-4H-pyran in living cells

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Science China Chemistry 2016年第1期59卷 62-69页

作者： xumeng wu andong shao shiqin zhu zhiqian guo weihong zhu Shanghai key laboratory of functional materials Chemistry Key Laboratory for Advanced Materials and Institute of Fine ChemicalsEast China University of Science and TechnologyShanghai 200237China

Glutathione(GSH)plays a critical role in maintaining oxidation-reduction homeostasis in biological *** the detection of GSH by fluorescence sensors is limited by either the short wavelength emission or the poor photostability,a highly stable colorimetric and ratiometric NIR fluorescent sensor(DCM-S)for GSH detection has been constructed on the basis of dicyanomethylene-4H-pyran(DCM)*** specific disulfide bond is incorporated via a carbamate linker as the GSH responsive group,which simultaneously blue-shifts and quenches the *** addition of GSH,DCM-S exhibits outstanding colorimetric(from yellow to red)and ratiometric fluorescent response with the 6-fold enhancement of NIR fluorescence at 665 nm in quantum *** importantly,the GSH-treated DCM-S(DCM-NH_2 actually)possesses 20-fold longer fluorescence half-life period as well as much better photostability than the FDA-approved ***,the ratiometric detection of GSH is also successfully operated in the living cell imaging,exhibiting NIR fluorescence and large Stokes shift(215 nm)with nearly no background fluorescence *** a consequence,DCM-S can be utilized as colorimetric and ratiometric NIR fluorescent sensor for GSH,with a great potential in the development of GSH-induced drug delivery system.

关键词： near-infrared GSH ratiometric colorimetric fluorescent sensor

SOMO-HOMO level conversion in triarylmethyl-cored N-heterocyclic carbene-Au(I)complexes triggered by selecting coordination halogens

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Chinese Chemical Letters 2024年第11期35卷 512-516页

作者： Le Zhang Hui-Yu xie xin Li Li-Ying Sun Ying-Feng Han key laboratory of Synthetic and Natural functional Molecule of the Ministry of Education Xi'an Key Laboratory of Functional Supramolecular Structure and MaterialsCollege of Chemistry and Materials ScienceNorthwest UniversityXi'an 710127China

Conventionally,organic radicals adhere to the Aufbau principle,the energy level of the singly occupied molecular orbital(SOMO)is not below the highest occupied molecular orbital(HOMO),but somewhat abnormal phenomena have appeared *** this study,we introduce a novel strategy by incorporating unique NHC-Au-X units into a tris(2,4,6-trichlorophenyl)methyl(TTM)system to create metal-involved open-shell complexes,denoted as TTM-NHC-Au-X(X=I,Br,or Cl).Density-functional theory calculations were used to predict an inversion in the energy of the SOMO and highest doubly occupied molecular orbital(HOMO)of TTM-NHC-Au-I,which is supported by experimental *** radicals TTM-NHC-Au-X demonstrated distinct properties with different coordinated *** radical behaviors have been investigated by EPR,UV-vis spectroscopy and cyclic voltammetry,additional structural information provided by structurally comparing related the precursor complexes given by X-ray ***-NHC-Au-I with SOMO-HOMO conversion(SHC)features a highly thermal decomposition temperature up to 305℃.Furthermore,the photostability of TTM-NHC-Au-I was found to be 75and 23 times greater than that of TTM-NHC-Au-Br and TTM-NHC-Au-Cl,*** findings provide valuable insights into the structural and electronic design principles governing the occurrence of SOMO-HOMO conversion in open-shell systems.

关键词： SOMO-HOMO conversion N-heterocyclic carbenes Aufbau and non-Aufbau Electronic structure Halogen atoms Radical

Effects of Yttrium Ion on Formation Mechanism of ZrO_2-Y_2O_3 Ceramic Coatings Formed by Plasma Electrolytic Oxidation on Al-12Si Alloy

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Journal of Wuhan University of Technology(materials Science) 2014年第5期29卷 1044-1048页

作者：王萍 LI Jianping GUO Yongchun YANG Zhong WANG Jianli Shaanxi key laboratory of Photoelectric functional materials and Devices Xi'an Technological University

ZrO2-Y2O3 ceramic coating was produced by plasma electrolytic oxidation （PEO） on ZAlSil2Cu3Ni2 alloy. The microstructure and phase composition of the coating were investigated by SEM and XRD.： The results show that adding an appropriate amount of yttrium ion can improve the growing rate of ceramic coating at different oxidation stages and decrease arc voltage. The thickness of ZrO2-Y2O3 coating is 16 μn thicker than that of ZrO2 coating and the maximum oxidation rate improves by 0.6 μm/min. In addition, the arc voltage decreases from 227 to 172 V. It can be seen that the rate of oxidation firstly increases to some extent and then decreases with the content of yttrium ion increasing. The growth rate reaches the maximum while the content of yttrium ion is 0.05 g-L-1The maximum thickness is 90 μ*** to ZrO2 coating, the micropores of ZrO2-Y2O3 coating are less and the ceramic layer is repeatedly deposited by ZrO2 and Y2O3 ceramic particles. Meanwhile, the binding force between coating and substrate is better and the coating is uniform and compact. The ceramic layer is mainly composed of c-Y0.15Zr0.85O1.93□0.07, m-ZrO2, α-Al2O3, ,γ-Al2O3 and Y2O3. It is indicated that ZrO2 has beert fully stabilized by yttrium ion through the formation of solid solution.

关键词： Al-12Si alloys yttrium ion plasma electrolytic oxidation ZrO2-Y2O3 ceramic coating

Stimuli-Responsive Interconversion between Poly-NHC-Based Organometallic Assemblies and Their Self-Aggregated Dimers

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Chinese Journal of Chemistry 2024年第22期42卷 2840-2844页

作者： Guang-Feng Jin Ying-Feng Han key laboratory of Synthetic and Natural functional Molecule of the Ministry of Education Xi'an Key Laboratory of Functional Supramolecular Structureand MaterialsCollege of Chemistry and Materials ScienceNorthwest UniversityXi'anShaanxi 710127China

Comprehensive Summary Poly-NHC-based organometallic assemblies 3-PF6,3-SbF6 and 3-OTf were obtained and verified by NMR spectroscopy,ESI mass spectrometry and single-crystal X-ray diffraction *** structural interconversion was observed between the poly-NHC-based organometallic assemblies and their self-aggregated dimers in solution affected by concentration,solvent and metal ion.1H NMR spectra of assembly 3-PF6 in CD3CN at different concentrations demonstrated controllable structural interconversion,and 19F NMR spectrum of assembly 3-PF6 at high concentration further evidenced the presence of the free hexafluorophosphate anion and encapsulated hexafluorophosphate anion for its two sets of *** addition,single-crystal X-ray diffraction analysis provided clear evidence that in the solid state,two assemblies 3-PF6 were vertically stuck,forming a self-aggregated dimer with an encapsulated hexafluorophosphate *** the reversible structural interconversion is beneficial for revealing the intrinsic nature on the atom level and paving the way to design the stimuli-responsive functional system.

关键词： N-Heterocyclic carbene Organometallic assemblies Self-aggregated dimer Stimuli-responsive Structural interconversion Concentrationl Solvent Metalion